SyntheticWidth: MediumLength: Fits true to sizeGel Cushioning System Attenuates shock during impact and toe-off phases, and allows movement in multiple planes as the foot transitions through the gait cycle.Flexion Fit Proprietary upper which provides form fitting comfort without sacrificing support.P.H.F. (Personal Heel Fit) 2 layers of memory foam line the collar and mold to the athlete's heel, creating a personalized fit.